Table 2. Mercury concentrations in vegetables and grains grown near coal-fired power plants.

		Mercury concentration (μg/kg Fresh Weight)
Samples		Location A1	Location A2	Location B1	Location B2	Location B3	Location B4	Control Sample#
Leafvegetables	Lettuce	39.04 ± 4.41*	22.70 ± 1.81*	21.03 ± 0.16*	19.41 ± 1.16*	9.17 ± 0.52*	7.23 ± 0.57*	0.35 ± 0.10
	Amaranth	46.40 ± 2.33*	27.76 ± 1.13*	29.29 ± 5.06*	7.50 ± 0.21*	5.52 ± 0.86*	3.64 ± 0.37*	0.28 ± 0.21
	Water spinach	86.69 ± 2.16*	69.02 ± 5.17*	54.46 ± 4.55*	49.19 ± 0.28*	38.97 ± 3.43*	23.88 ± 1.28*	0.85 ± 0.22
FruitVegetables	Tomato	71.80 ± 11.95*	29.80 ± 3.03*	76.33 ± 5.47*	57.09 ± 8.33*	29.07 ± 1.45	9.79 ± 0.43*	0.73 ± 0.36
	Eggplant	42.37 ± 4.24*	13.07 ± 1.73*	43.36 ± 1.71*	25.02 ± 1.80*	14.61 ± 2.95*	3.25 ± 0.41*	0.43 ± 0.39
	Pepper	49.66 ± 1.40*	14.65 ± 1.63*	62.09 ± 3.22*	30.89 ± 2.19*	15.75 ± 1.27*	4.69 ± 0.13	0.93 ± 0.84
	Cucumber	38.45 ± 1.40*	9.87 ± 0.11*	18.21 ± 1.19*	16.94 ± 0.66*	10.09 ± 0.40*	2.18 ± 0.34*	0.87 ± 0.24
	Cowpea	56.31 ± 4.03*	11.63 ± 1.36*	57.30 ± 9.24*	21.75 ± 1.55*	18.46 ± 0.61*	11.20 ± 0.95*	0.93 ± 0.13
Grain	Rice	62.95 ± 3.88*	29.24 ± 2.04*	59.21 ± 4.36*	43.30 ± 2.19*	37.15 ± 2.39*	24.99 ± 1.99*	0.55 ± 0.48
	Maize	21.02 ± 1.98*	6.68 ± 1.002*	21.18 ± 0.67*	4.68 ± 0.707*	1.06 ± 0.08*	0.55 ± 00.63	0.72 ± 0.19

Sampling sites are marked in Fig. 1. ^#Control samples were collected from a grocery store > 55 km from Power Plant A. Bolded numbers indicate that the mercury concentration in samples exceeded the maximum allowed mercury level of 10 μg/kg FW in vegetables and 20 μg/kg FW in grains (food safety standard in China, GB 2762–2012)²¹. *The mercury concentration between the same kind of vegetable and grain samples collected from coal-fired power plant regions and grocery store was significantly different at P = 0.05 level.